Solve 20a+a-1=

$$20 a + a - 1 =$$

Differentiate w.r.t. a

$$21$$

Steps Using Derivative Rule for Sum

Combine 20a and a to get 21a.

$$\frac{\mathrm{d}}{\mathrm{d}a}(21a-1)$$

The derivative of a polynomial is the sum of the derivatives of its terms. The derivative of a constant term is 0. The derivative of ax^{n} is nax^{n-1}.

$$21a^{1-1}$$

Subtract 1 from 1.

$$21a^{0}$$

For any term t except 0, t^{0}=1.

$$21\times 1$$

For any term t, t\times 1=t and 1t=t.

$$21$$

Evaluate

$$21a-1$$

Solution Steps

Combine 20a and a to get 21a.

$$21a-1$$